In this equation, Sodium (Na) and Hydrogen (H) atoms are not balanced. There are 2 atoms of Sodium (Na) on Right Hand Side, so we can multiply NaOH with 2 on Left Hand Side. This balances the Sodium (Na) atoms. Now, Hydrogen (H) and Oxygen (O) atoms are unbalanced. Again, we multiply 2 with Water on Left Hand Side. Thus all the elements are balanced.